His favorite author was Joseph Conrad. In the 1950s he was cast as Kurtz in a production of Conrad's "Heart of Darkness" on "Playhouse 90" (1956).
His first Broadway play was "Arsenic and Old Lace" in a role that was written for him. He played Jonathan Brewster, whose face has been changed by a disreputable plastic surgeon named Dr. Einstein so that he now looks like Boris Karloff. He also performed the role in the road company of this production.
His siblings pushed him toward a career in government service, but he turned to acting instead.
His voice was the basis for future Tony the Tiger commercials by Kellogg's.
In contrast to the image he presented in most of his films, the private Karloff was, by every account, a quiet, bookish man off- screen. A true gentleman, he had many friends, both in and out of show business, and he was particularly fond of children. For the latter, among other things, he recorded many successful albums of children's stories.
In his book, Mark of the Werewolf, novelist Jeffrey Sackett has a character named William Henry Pratt. The character's description fits Karloff perfectly.
In the final years of his life, walking, and even just standing, became a painful ordeal. Some directors would change the script to place Karloff's character in a wheelchair, so that he would be more comfortable.
Is portrayed by Jack Betts in Gods and Monsters (1998)
Karlff was one of the twelve original founders of the Screen Actor's Guild and held SAG #9.
Karloff got the role in "The Criminal Code," a breakthrough role for him because he was broke. He couldn't go to the Masquers because he couldn't pay his dues and couldn't afford his second choice, a cup of coffee, so he went to Actors' Equity, where he learned that there was casting for the part.
Maintained an apartment in New York's The Dakota apartment house.
Never legally changed his name to Boris Karloff. He always signed contracts and documents as "William Henry Pratt AKA Boris Karloff".
Often thought of as a very large man, he was in reality a slim man of medium height. He wore huge lifts and much padding to give him the massive look as Frankenstein's monster.
On June 30, 1912, a then-unknown Karloff had taken some time off to canoe while touring around the city of Regina, Saskatchewan, Canada. When he came back to the city, he returned to find his accommodation had been destroyed by a tornado that killed 28. He organized a concert that raised some much needed funds for the city.
Once did a television commercial for A-1 Steak Sauce.
Pictured on two of a set of five 32¢ US commemorative postage stamps, issued 30 September 1997, celebrating "Famous Movie Monsters". He is shown on one stamp as the title character in The Mummy (1932) and on the other as the monster in Frankenstein (1931). Other actors honored in this set of stamps, and the classic monsters they portray, are Lon Chaney as The Phantom of the Opera (1925); Bela Lugosi as Dracula (1931); and Lon Chaney Jr. as The Wolf Man (1941).
Played cricket for Enfield Cricket Club (just north of London, England) before emigrating, and the club has his picture hanging in the pavilion.
Raised rare Bedlington Terriers while he lived in Brentwood, CA. One day he was walking them with his four-year old daughter Sara Karloff when they broke free and they ran up to an inebriated man stumbling down the street. The drunk begged Karloff for a ride to Cedars of Lebanon Hospital, claiming he "just saw three sheep bark!" Karloff obliged.
Received a Tony nomination in 1956 for his dramatic role in 'The Lark.'
Refused to reprise his role as the Frankenstein Monster in Bud Abbott and Lou Costello Meet Frankenstein (1948), because he felt spoofs wouldn't sell to the audience. He did agree to do publicity for the film and posed for pictures of himself going to see the film.